1. Field of the Invention
Embodiments of the present invention relate at least to a system, medium, and method for providing a thumbnail visualizing a plurality of features within a plurality of photographs to facilitate the search of the plurality of photographs, and more particularly, to a system, medium, and method for classifying photographs into groups based on metadata embedded in respective photograph files and generating a combinational thumbnail by combining object images extracted from individual representative photographs of the respective groups.
2. Description of the Related Art
In recent years, with the rapid proliferation of digital photographs and individuals being capable of easily photographing images using portable imaging devices (e.g., digital camcorders and digital cameras), one problem that has surfaced is the difficulty in organizing the hundreds, if not thousands, of photographs taken by the individuals.
In the case of a digital camera, for example, it is almost impossible to independently classify a huge number of photographs, e.g., due to restricted interface in device manipulation. Thus, photographs taken using a digital camera are typically automatically titled and stored. In this case, however, it is quite difficult for a user to recognize when and why an individual photograph file was shot based solely on the title of the photograph file.
One approach to overcome this problem is to allow the user to group photograph files into folders, each made based on an event common to photographs, and individually title each folder according to the corresponding event. However, this approach is typically bothersome to the user because the user needs to personally input the title of each folder based on an event common to photograph files right after shooting the photograph files, or upon adding the photographs to a digital library, e.g., on a personal computer. In addition, when the numbers of folders increase and time lapses, it becomes more difficult to remember the separate contents of each folder just based on the title of the folder.
To solve the above problems, many approaches have been proposed. For example, to compensate for drawbacks of this “titling” approach, e.g., corresponding to a conventional event identifier, the Windows XP operating system of the Microsoft Corporation presents thumbnails of four representative photographs for each folder on the icon representing the folder. In other words, thumbnails are displayed as the folder icon so that a user can look at the four thumbnails and identify image files stored in the folder.
However, a thumbnail is an icon made by reducing an image made up of several millions of pixels to a size of merely several thousands of pixels, and therefore, detailed information of objects within the original image is lost during the image reduction. As a result, it is difficult to distinctively identify different objects within the thumbnail image.
To overcome the problem of the above-described thumbnail approach, Japanese Patent Publication No. 2000-295570 (entitled “Electronic Camera Device”) discusses a technique of extracting a predetermined area including an auto focus (AF) region in an entire photographed image and creating a thumbnail image from the extracted predetermined area, instead of reducing the entire photographed image, thereby anticipating that the AF region of the image was the region the user believed important.
However, often, the AF region of an image is not representative of the region of the image or objects with the image the user was intending to emphasize or capture, e.g., when a user takes a picture of people and scenery, he/she may focus on the people using a half shutter press, to set the auto focus distance, and then move the camera to obtain a clear image of both of the people and scenery. Similarly, the original AF region while taking a photograph may include people in most of the photographs, such that most of the corresponding thumbnail images include the people's faces, though the surrounding scenery may actually be the emphasis of the photograph. In addition, when a photograph is added to a digital library on a personal computer, for example, and such original AF information is not known, then the AF region may be anticipated, e.g., based upon the usual AF region of images.
In this condition, when many folders include photographs of the same people shot at different locations, thumbnail images of the folders would all correspond to face regions, and therefore, it is difficult to distinguish the folders from one another. It has been reported that people most frequently uses three kinds of information, i.e., “when”, “where”, and “people” when searching for particular photographs, J. Huang, et al., Image Indexing Using Color Correlograms, IEEE Conf. Computer Vision and Pattern Recognition, 1997.
Accordingly, the inventors of the present invention have found that to more effectively search existing thumbnail picture data, it is desirable to enable a user to easily recognize when and where photographs in a folder were shot and who the photographs are based on through thumbnail picture data displayed in the folder.